Users scrambled for answers as they received Error 502 messages and low processing speeds. Despite the incident only lasting a brief time in its totality, user frustration and confusion generated quite a bit of speculation in the online community – most notably, “What was the main cause of the downtime?”

We now appear to have an answer. The company recently issued an incident report, noting that it had attempted to issue an update to its load balancing system – responsible for allowing users to access service via the company’s data centers.

“A bug in the software update caused it to incorrectly interpret a portion of Google data centers as being unavailable. The Google load balancers have a failsafe mechanism to prevent this type of failure from causing Google­wide service degradation, and they continued to route user traffic. As a result, most Google services, such as Google Search, Maps, and AdWords, were unaffected,” stated the company via the report.

The services that did, however, face downtime included Gmail, Google Drive, among a few others. So why only the partial outage? Google noted those relied on “specific data center information to efficiently route users’ requests.”

The company, meanwhile, is taking a number of steps including addressing load balancing updates to ensure the issue doesn’t occur again.